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<H1 class="no-header">curs_variables 3x</H1>
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<STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>                                          <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>




</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>COLORS</STRONG>, <STRONG>COLOR_PAIRS</STRONG>, <STRONG>COLS</STRONG>, <STRONG>ESCDELAY</STRONG>, <STRONG>LINES</STRONG>, <STRONG>TABSIZE</STRONG>, <STRONG>curscr</STRONG>, <STRONG>newscr</STRONG>,
       <STRONG>stdscr</STRONG> - <STRONG>curses</STRONG> global variables


</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
       <STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>

       <STRONG>int</STRONG> <STRONG>COLOR_PAIRS;</STRONG>
       <STRONG>int</STRONG> <STRONG>COLORS;</STRONG>
       <STRONG>int</STRONG> <STRONG>COLS;</STRONG>
       <STRONG>int</STRONG> <STRONG>ESCDELAY;</STRONG>
       <STRONG>int</STRONG> <STRONG>LINES;</STRONG>
       <STRONG>int</STRONG> <STRONG>TABSIZE;</STRONG>
       <STRONG>WINDOW</STRONG> <STRONG>*</STRONG> <STRONG>curscr;</STRONG>
       <STRONG>WINDOW</STRONG> <STRONG>*</STRONG> <STRONG>newscr;</STRONG>
       <STRONG>WINDOW</STRONG> <STRONG>*</STRONG> <STRONG>stdscr;</STRONG>


</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
       This page summarizes variables provided by the <STRONG>curses</STRONG> library.  A  more
       complete description is given in the <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG> manual page.

       Depending  on  the  configuration,  these  may  be actual variables, or
       macros (see <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG> and <STRONG><A HREF="curs_opaque.3x.html">curs_opaque(3x)</A></STRONG>) which  provide  read-
       only  access  to  <EM>curses</EM>'s  state.  In either case, applications should
       treat them as read-only to avoid confusing the library.


</PRE><H3><a name="h3-COLOR_PAIRS">COLOR_PAIRS</a></H3><PRE>
       After initializing curses, this variable contains the number  of  color
       pairs  which  the  terminal  can  support.  Usually the number of color
       pairs will be the product <STRONG>COLORS</STRONG>*<STRONG>COLORS</STRONG>, however  this  is  not  always
       true:

       <STRONG>o</STRONG>   a few terminals use HLS colors, which do not follow this rule

       <STRONG>o</STRONG>   terminals  supporting  a  large number of colors are limited by the
           number of color pairs that can be represented  in  a  <EM>signed</EM>  <EM>short</EM>
           value.


</PRE><H3><a name="h3-COLORS">COLORS</a></H3><PRE>
       After  initializing curses, this variable contains the number of colors
       which the terminal can support.


</PRE><H3><a name="h3-COLS">COLS</a></H3><PRE>
       After initializing curses, this variable  contains  the  width  of  the
       screen, i.e., the number of columns.


</PRE><H3><a name="h3-ESCDELAY">ESCDELAY</a></H3><PRE>
       This variable holds the number of milliseconds to wait after reading an
       escape character, to distinguish between an individual escape character
       entered on the keyboard from escape sequences sent by cursor- and func-
       tion-keys (see <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>).


</PRE><H3><a name="h3-LINES">LINES</a></H3><PRE>
       After initializing curses, this variable contains  the  height  of  the
       screen, i.e., the number of lines.


</PRE><H3><a name="h3-TABSIZE">TABSIZE</a></H3><PRE>
       This  variable  holds  the number of columns used by the <EM>curses</EM> library
       when converting a tab character to spaces as it adds the tab to a  win-
       dow (see <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG>.


</PRE><H3><a name="h3-The-Current-Screen">The Current Screen</a></H3><PRE>
       This  implementation  of  curses uses a special window <STRONG>curscr</STRONG> to record
       its updates to the terminal screen.

       This is referred to as the "physical screen"  in  the  <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG>
       and <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG> manual pages.


</PRE><H3><a name="h3-The-New-Screen">The New Screen</a></H3><PRE>
       This  implementation of curses uses a special window <STRONG>newscr</STRONG> to hold up-
       dates to the terminal screen before applying them to <STRONG>curscr</STRONG>.

       This is referred to as the "virtual  screen"  in  the  <STRONG><A HREF="curs_kernel.3x.html">curs_kernel(3x)</A></STRONG>,
       <STRONG><A HREF="curs_refresh.3x.html">curs_refresh(3x)</A></STRONG> and <STRONG><A HREF="curs_outopts.3x.html">curs_outopts(3x)</A></STRONG> manual pages.


</PRE><H3><a name="h3-The-Standard-Screen">The Standard Screen</a></H3><PRE>
       Upon  initializing curses, a default window called <STRONG>stdscr</STRONG>, which is the
       size of the terminal screen, is created.   Many  curses  functions  use
       this window.


</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       The   curses  library  is  initialized  using  either  <STRONG><A HREF="curs_initscr.3x.html">initscr(3x)</A></STRONG>,  or
       <STRONG><A HREF="curs_initscr.3x.html">newterm(3x)</A></STRONG>.

       If <STRONG>curses</STRONG> is configured to use separate curses/terminfo libraries, most
       of these variables reside in the curses library.


</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       <STRONG>TABSIZE</STRONG>  is  a feature of SVr4 curses which is not documented by X/Open
       curses.

       <STRONG>o</STRONG>   In SVr4 curses, <STRONG>TABSIZE</STRONG> is initially set from the terminal descrip-
           tion's  <STRONG>init_tabs</STRONG> capability.  After that, it can be altered by the
           applications using SVr4 curses.

           SVr4 curses uses the current value of <STRONG>TABSIZE</STRONG> to compute the  posi-
           tion  of  tabstops  for  updating both the virtual screen with <STRONG>add-</STRONG>
           <STRONG><A HREF="addch.3x.html">ch(3x)</A></STRONG> as well as the physical screen with <STRONG><A HREF="curs_terminfo.3x.html">mvcur(3x)</A></STRONG>.

       <STRONG>o</STRONG>   This implementation uses the current value of <STRONG>TABSIZE</STRONG> only for  up-
           dating  the  virtual screen.  It uses the terminal description's <STRONG>it</STRONG>
           (<STRONG>init_tabs</STRONG>) capability for computing hardware tabs (i.e., tab stops
           on the physical screen).

       <STRONG>o</STRONG>   Other  implementations  differ.  For instance, NetBSD curses allows
           <STRONG>TABSIZE</STRONG> to be set through an environment variable.  This  implemen-
           tation does not.

           NetBSD curses does not support hardware tabs; it uses the <STRONG>init_tabs</STRONG>
           capability and the <STRONG>TABSIZE</STRONG> variable only for updating  the  virtual
           screen.

       <STRONG>ESCDELAY</STRONG> is an extension in AIX curses:

       <STRONG>o</STRONG>   In AIX, the units for <STRONG>ESCDELAY</STRONG> are <EM>fifths</EM> of a millisecond.

       <STRONG>o</STRONG>   The default value for AIX's <STRONG>ESCDELAY</STRONG> is 0.1 seconds.

       <STRONG>o</STRONG>   AIX  also enforces a limit of 10,000 seconds for <STRONG>ESCDELAY</STRONG>; this im-
           plementation currently has no upper limit.

       This implementation has long used <STRONG>ESCDELAY</STRONG> with units of  milliseconds,
       making  it  impossible to be completely compatible with AIX.  Likewise,
       most users have either decided to override the value, or rely upon  its
       default value.


</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>,   <STRONG><A HREF="curs_opaque.3x.html">curs_opaque(3x)</A></STRONG>,   <STRONG><A HREF="curs_terminfo.3x.html">curs_terminfo(3x)</A></STRONG>,   <STRONG><A HREF="curs_threads.3x.html">curs_threads(3x)</A></STRONG>,
       <STRONG><A HREF="term_variables.3x.html">term_variables(3x)</A></STRONG>, <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG>.



                                                            <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
<li><a href="#h3-COLOR_PAIRS">COLOR_PAIRS</a></li>
<li><a href="#h3-COLORS">COLORS</a></li>
<li><a href="#h3-COLS">COLS</a></li>
<li><a href="#h3-ESCDELAY">ESCDELAY</a></li>
<li><a href="#h3-LINES">LINES</a></li>
<li><a href="#h3-TABSIZE">TABSIZE</a></li>
<li><a href="#h3-The-Current-Screen">The Current Screen</a></li>
<li><a href="#h3-The-New-Screen">The New Screen</a></li>
<li><a href="#h3-The-Standard-Screen">The Standard Screen</a></li>
</ul>
</li>
<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
</ul>
</div>
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